Air heater



May 29, 1928. A1,671,183

A H. F. GAUSS AIR-HEATER Filed Jan. 14, 1926 2 sheets-sheet ll l 2- WIWHM, .f +5

TTR/VE Y6.

H. F.' GAUSS AIR HEATER May/@'29, 192s. 1,671,188v

Filed Jan. 14, 1926 'z sheets-sheet 2 A TTORA/EYJ.

Patented May 29, 1928.

UNITED STATES PATENT OFFICE.

HENRY F. GAUSS, OF MOSCOW, IDAHO, ASSIGNOR TO HEINE BOILER COMPANY, 0]l` ST. LOUIS, MISSOURI, A CORPORATION 0F MISSOURI.

AIR HEATER.

Application tiled January 14, 1926. Serial No..81,333.

This invention relates to heating devices of the kind that are used :for causing one gaseous medium to be heated by another gaseous medium of a higher temperature, and particularly air heaters of the recuperative type composed of a plurality Ofmetal plates combined in such a manner as to form air passageways and gas passageways arranged in alternate relation and disposed so as to cause the gases which escape from a boiler to flow through said gas passageways, and thus heat air which is being d iawn or forced through said air passageways to the furnace of the boiler.

lThe main object of my invention is to provide a iecuperative air heater of the plate type, that is eliicient, inexpensive to manufacture and of such construction that air cannot leak into the gas passageways, and thus reduce the temperature of the gases lflowing through said passageways.

Figure l of the drawings isr a side elevational view of an air heater constructed in accordance with my invention, combined with a water tube boiler.

Figure 2 is a front elevational View of said heater. v

Figure 3 Yis a vertical longitudinal sectional view of said heater, taken through one of the air passageways.v

Figure 4 is a horizontal transverse sectional view through a portion of the heater, illustrating the devices that are used at the intake ends and discharge ends of the air passageways to hold the plates spaced apart, saidview being taken on the line 4 4 of Figure 3.

Figure 5 is a horizontal transverse sectional view, taken through the intermediate portion of the heater, as, for example,`on the line 5 5 of Figure 3. f Figure 6 is a horizontal transverse sectional view similar to Figure 5, illustrating a slight modification of my invention.

Figure 7 is a horizontal transverse sec tional view similar to Figure 4, illustrating still another form of my invention; and

Figure 8 is a .horizontal transverse sectional view, similar to Figure 5 of an air heater of the kind shown in Figure 7 In the drawings A designates a boiler of any preferred type herein illustrated as a water tubeboiler and B designates an air heater arranged in such a manner that the gases which escape from said boiler will flow through said air heater and thus heat air which is being supplied to the furnace of the boiler to support combustion. As shown in Figure 1 the air heater B is arranged at the upper end of the boiler in the path of the escaping gases indicated by the arrows a: a fan or other suitable suction device C being used to cause the gases to fiow through the air heater and a blower or other suitable device D being used to cause air to flow through the heater B and then pass to the v grate or to the combustion chamber of the boiler as indicated by the arrows y.

The air heater B is made up of a plurality of thin flat metal plates l of substantially oblong shap(` in outline, arranged vertically in parallel relation, and flat metal bars andspacing devices combined with said plates in such a way as to form a plurality of openended gas passageways ai through which the gases flow longitudinally of the heater, and a plurality of air passageways y between said gas passageways, each of said air passageways being provided at one end with an inlet openiiio located in one side of the heater and provided at its opposite end with a discharge opening located in the opposite side .of the heater. In the form of my in- Vention herein illustrated the heater B is provided at its upper end with a tubular intake 2 common to all of the air passageways` y that projects laterally from the rear side of the heater, and said heater is provided at its lower end with a tubular discharge 3 common to all of the air passageways that projects forwardly from the front side of the heater, as shown in Figures l and 3.

The gas passageways f are formed by the plates 1 and flat metal bars 4 arranged between pairs of said plates at the longitudinal side edges of saine and extending the entire length of the heater, thus forming vertically-disposed gas passageways that have intake openings located in the bottom of the heater and discharge openings located in the top of the heater. The air passageways y are also formed by the plates 1 and by flat metal bars that are combined with said plates in such a way as to form air passageways between the gas passageways that have lateral intake openings in the rear side of the heater 'and lateral discharge openings in the front side of the heater. As shown in the drawings, the upper and lower ends of Athe air passageways y are closed by horizontally-disposed bars 5 that are arranged between the respective pairs of plates l, and the side edges of said air passageways are formed by short metal'bars 4*1 of less length than the bars 4, arranged between the respective pairs of plates 1 parallel to the bars 4 and extending from the ends of the hea-ter to the points where the intake and discharge openings of the air passageways are located. In order to hold the plates 1 spaced apart at the points where the intake and discharge openings o the air passageways y are located, spacing devices 6 are arranged between the plates 1 in the inlet and discharge o enings of the air passageways, as shown in igure 4.

Any suitable means can be used for combining the plates 1 with the bars and spacing devices above referred to, but I prefer;

t0 clamp said parts securely together by long bolts 7 that extend transversely of the heater and which pass through the plates 1, bars 4 and 4 and spacing devices 6, as shown in Figures 4 and 5, the spacing devices 6 being of tubular form. An air heater of the construction above described is strong and rigid and it is inexpensive to manufacture, as it is built up principally of fiat metal plates and dat metal bars that are clamped together by transversely-disposed bolts which pass through aligned openings in said plates and bars. Moreover, such a heater is exceptionally ecient, as the air Hows through the heater in a direction opposite to the flow of the gases, and the mein-lv bers that divide the -air passageways from the gas passageways consist of relatively thin metal plates that absorb heat rapidly from esca ing gases and transmit said heat lto the in owin air. The air passageways y are prefera ly provided with y horizontally-disposed Ibames 8 arranged in stag gered relation, as indicated in Figure 3, so as to cause the air to make a plurality of passes and dow in a zig-zag path through the air passageways of the heater. After the plates 1, bars 4 and 4 and spacing de vices 6 have been assembled and clamped together the joints in the iront and rear sides of the heater -formed by the longitudinal side edges ont the plates '1 and the bars 4 and 4 interposed between the same are sealed, preferably by welding, as indicated by the reference character 9 in Figure. 5, so as to eliminate the possibility of air entering the gas passageways w', and thus reducing the temperature of the gases passing through the heater.

In Figure '6 Il have illustrated an air heater that embodies all of the desirable 'features and characteristics et the air heater shown in Figures 4 and 5 and which has the added advantage ofjrequiring only one-half the number 0f welded joints tofproduce gas passageways whose longitudinal side edges are air-tight. In said heater every alternate plate 11 is provided at one ofits longitudinal edges with an integral, laterallyvprojecting fiange 10 that 1s connected by a welded joint 9a to the adjacent longitudlnal' side edge of the plate 1"' with which it cooperates to form a gas passageway, the flanges 10 being arran ed on the outsldes of the long bars 4 that orm the longitudinal side edges of the gas passageways.

In instances where it is desired to entirely eliminate welded joints at the longitudinal side edges of the plates which separate the air passageways ,from the gas passageways, without however, impairing the eiliciency of the heater, the heater can, be built up of flat, oblong-shaped plates 1, as shown in Figures 7 and 8, with pairs of long and shortspacing bars and asbestos packing material arranged between the longitudinal side edges of said plates at thefront and rear sides ofv the heater.l Thus, as shown in Figure 8, pairs of long bars 40 can be arranged be,- tween the plates 1 at the front and rear sides of the heater, and the space between said bars can be lled with asbestos or other packing material 41. Similar pairs of short bars 4()a are arranged between the-plates l to form the edge walls'o the air passageways y', the spaces between said bars 40 also being lled with asbestos. At the points where the inlet and discharge openlngs of the air assageways are located tubular s acing evices 6*' are arranged between t e pairs of plates 1 that constitute the air passageways, as shown inv Figure 7.

It wi l, of course, be understood that it is immaterial, so far as my inventionis concerned, whether the air heater B is arranged in a vertical position or in a horizontal pon sition, and it is also immaterial which particular group of passageways in said heater is used for thev escaping gases and which group of passageways is used for the inowf mg air. Likewise, it is immaterial what means is used to produce tight joints at the longitudinal side edges of the gas passageways, so long as the side edges or longitudi nal edges of the two grou s or passageway/s of the heater are formed y flat metal bars that are arran ed between the plates that separate the in lowing air from the escaping gases,

Having thus described my inventiomwhat I claim as new and desire tol secure by Letters Patent is:

An air heater composed of a plurality ot flat metal plates of the'same sine arranged in parallel relation, hat metal bars of substantiall the same length as said plates arranged etween the longitudinal edge pore lll@ lll

ias

tions of pairs of said plates so as to torna j passagewa'ys having inlet and discharge spacing devices arranged between the reopenings located at the ends of the heater, spective pairs of plates in said lateral inlet fiat metal bars of less length than the plates and discharge openings, and bolts that pass l0 arranged between the respective pairs of transversely through said plates, bars and 5 lates so as to form passageways havin spacing devices so as to clamp them tightly ateral inlet and discharge openings locate together. at the frontand rear sides of the heater, HENRY F. GAUSS. v 

